Tube cross connection



Jan. 23, 1951 J, BRADF'IELD TUBE oRoss CONNECTION 2 Sheets-Sheet 1 Filed June 5, 194'? Q Q Q 2 w n Jan. 23, 1951 J. BRADFIELD TUBE cRoss CONNECTION 2 Sheets-Sheet 2 Filed June 3, 1947 49 INvENToR,

` JOSEPH L. BRADHELD,

'BY #0V/ML@ 5E-TOR NE Y.

Patented Jan. 23, 1951 UNITED STATES PATENT OFFlCEv TUBE CROSS CONNECTION Joseph L. Bradeld, Indianapolis, Ind.

Application June 3, 1947, Serial No. '752,059

2 Claims.

This invention relates to a radiant heating system, and to the method or the process of mak ing lateral flow line connections with supply and return dow lines. A primary object of the invention is to provide a mechanical combination oi supply and return now' lines from and to which are connected loops or laterally extending lines, connected to those supply and return flow lines in a manner permitting the lateral lines to be imbedded in the plaster of a ceiling or panels and the like; permitting the lateral loop ends to pass under one of the dow lines without increasing the normal thickness of the plaster or causing a bend in that passing portion; and more importantly permitting the positioning of the supply and return ow lines entirely above the plaster to prevent any appreciable direct conduction of heat primarily from the supply line to the plaster.

In the system herein described, a fluid is circulated through a supply line from a heat source and returned back to that source through a return iow line. A plurality of loops, preferably of such material as copper, extend laterally from these two iloW pipes which are normally positioned centrally across the panel from Which the heat is to be radiated. These loops have one end connected to the supply line and the other end to the return line. The connections between the loops in these lines are extremely important in the present invention in order, not only to permit one end portion of a loop passing across one ovv line to the other Without a downward bend, but also to have the axes of these loops so positionedthat the supply and return lines are spaced entirely thereabove so as to locate those lines up out of the plaster.

There may be as many as thirty or more lateral loops connected in parallel to the suppiy and re` turn lines for one room.. Heretofore it has been common practice to bury not only these lateral lines or loops in the plaster, but also to bury those supply and return lines. This resulted in a very marked drop in temperature of the fluid between the inlet end and the far end across a room in the supply line due` to exchange of heat by con`v duction. lossr` to the plaster. This resulted, inV

lserioustemperature shading acrossthe room in 2 temperature shading across the panel of the radiated loops.

In the construction herein shown and described the supply line as well as the return line is above the lower face of the ceiling lath and therefore is out of contact with the plaster therebelow. The supply and return lines thus exposed above, the plaster may be covered with suitable heat insulating material. The result is that there is practically no drop Ain the temperature oi the fluid as it is owed through the supply line resulting in. iluid entering all of the lateral loops or lines at practically the same temperature.

Furthermore, it has also been found necessary' to make a fitting or cross connection with these supply and return flow lines which Will have such a form that there Will be no murmuring or rippling noises arising from flow of the Water in these supply lines as the water travels across these connections. Normally, cross connections. with the supply and ow return lines are made. at frequent intervals therealong, such for eX- ample, as spacings on the order of from six to nine inches apart. This means that there are a large number of cross connections required to install a complete radiant system. Therefore, itis necessary that these connections be made not only exceedingly durable in respect to possible leakage, but that they be made in the most inexpensive manner as Well as be made to permit quick connections therewith at the ceiling level with the ends of the lateral pines or tubes, these cross connections being sufficiently substantial to permit the insertion of the ends of the tube within the connections for soldering or brazing. Preferably the material used in the type of heating herein indicated consists of cop per tubing.

An important object of the invention is to pro-f vide supply and return flow tubes with multiple outlets over which cross tubes are secured in position in such manner that the cross tube diameter is substantially tangential to the diameter of the Iiow tube and the flow tube is sufficiently olset or bulged about. its opening into the cross tube to permit the cross tube to be saddled across the ow tube and yet maintain the relative position thereof as indicated. A stillV further important object. of the inventionis. to provide a method fer quickly and safely forming the bulged zones inthe now tube and at the same time forming elliptical or elongated openings through that bulged. zione.. y

. These. andfmany other objects and advantages Willvbeco'rne apparent to those, versed in` the art 3 in the following description of one particular form of the invention as illustrated in the accompanying drawing in which:

Fig. 1 is a View or bottom plan of a length of a now tube initially drilled at cross connection spacings;

Fig. 2, a View in central longitudinal section through the flow tube with a bulge forming tool therewithin Fig. 3, a view in transverse section on the line 3 3 in Fig. 2;

Fig. 4, a view in central longitudinal section through a length of the ow tube with the tool therewithin and bulged zones formed;

Fig. 5, a view in transverse section on the line 5 in Fig. 4;

Fig. 6, a view in bottom plan View of the flow tube with the bulge formed and a cross tube connector across one bulge;

Fig. 7, a view in transverse section on the line 'I--'I in Fig. 6;

Fig. 8, a detail in perspective of the tool eX- panding member;

Fig. 9, a view in perspective of the end portion of the outer shell of the tool;

Fig. is a detail in section of a. fragmentary portion of a ceiling construction to which the invention is applied;

Fig. 11, a section on the line I I-II in Fig. 10; and

Fig. 12, a view from the under side of a fragmentary portion of the ceiling with a portion of plaster removed.

Referring to the drawing in which like characters of reference indicate like parts, a fiow tube I0 made of copper is drilled at the desired cross connection locations to form the circular holes II therein. It is understood of course, that the length of the tube I0 may be made to be that which can be conveniently handled. For example, a length of six feet may be employed without difficulty in the forming of the cross connections.

I provide a tool which has a tubular shell or sleeve I2 with an external diameter suiciently less than the internal diameter of the tube I!) to permit the sleeve I2 to be inserted within the tube Il] with a free, sliding t. Toward one end of the shell I 2, Fig. 9, a window I3 is cut across the shell I2 down to about the diametrical plane.

, Within the shell I2 is inserted a cam or wedge member I4. This member I4 has a cylindrical head I5 of a diameter to produce a sliding` t between it and the inside of the shell I2. From this head I5, the member III/slopes by a flat face I6 gradually downwardly to terminate substantially within'the diametrical plane of the head I5. The under side of the member I4 is curved to conform with the inside curvature of the shell I2. A block I1 substantially semi-cylindrical in shape, Fig. 8, is provided to have a length slightly less than the length of the window I3 so that the block Il' may be slidingly entered between the ends of that window across the shell I2 to have the under face of the block I1 rest by its outer end portions across the shell wall portions deiining the longitudinal ends of the window I3. When the block II is thus positioned its curved surface is of the same curvature as that of the outer face of the shell I2. A keeper I8, Fig. 8, generally in the shape of a hairpin, has its outer looped end I9 preferably secured to the outerl end ofthe shell I 2A in any suitablamannersuch as by brazing, to have the keeperisjextend within the 'shell I2 and enter by its two prongsl loosely within spaced apart holes 20 and 2I drilled longitudinally through the block I'I near its base. To facilitate the mounting of the keeper I8 and to have its prong normally parallel with the axis of the shell I2, the keeper is provided with bends 22 and 23 adjacent the outer looped end so that the end I9 may be curved around upwardly against the outer end of the shell I2. Preferably ior locating purposes the top side of the black Il is provided with a bore 24 equal in diameter to or slightly less than the diameter of the holes II.

The shell I 2 with the block I 'I mounted thereon as above indicated is inserted into the tube I0, and as indicated in Fig. 2, the bore 24 of the block I'I is centered under a tube hole II, a left hand hole in the present showing. Then the cam member or bar I4 is entered in the shell I2 to have its thinner end carried under the block I'I. n Pressure is applied to the bar head I5 by any suitable means such as through a rod 25, Fig. 4, operated by a hydraulic cylinder (not shown) and the bar I4 is forced longitudinally along within the shell I2 (the shell I2 remaining stationary relative to the tube I6) whereby the block Il is forced laterally against the limited area of the tube i6 which is exposed over the block I'I. As indicated in Fig. 4, in reference to the right hand hole II, the block I1 will stretch the wall of the tube I6 to form the bulge 26. Upon stretching the tube wall to form this eX- tended bulge 2 6 the hole I I assumes the generally elliptical shape as indicated in Fig. 6 which is the final desired shape of this hole II. This operation of forming a bulge 26 about each hole II and the production of the elliptical shape of the hole is repeated at the position of each hole II along the tube I6. A cross tube 2l of much smaller diameter than that of the flow tube II) is cut away on one side by any suitable means such as by a circular milling cutter to a Sufficient depth to permit the connector tube 21 to fit across the bulge 26 and have the margin of the opening in it fit around the margin of the hole Il, Fig. 7. The depth of the cut into the connector tube 2? is made to be su-ch that the under side of the connector tube 21, Fig. '7, is tangential to the outer side of the flow tube I0 between bulges 26. The connector Z'I is brazed in position across the hole II to X it and to seal the joint therearound against leakage, a fillet 28 being preferably run around the joint to reinforce the connection.

The connector tube 2'! is initially provided with spaced apart prick punchings 29 and 3E! to form the rounded projections 3l and 32 within the bore of the tube. These projections 3! and 32 serve as limiting stops against which the end of the lateral radiating tube 33 may be abutted when that end is inserted within the connector tube 21. These ends are sweated to the connector tubes 2 for leak-proof connections.

In the process of forming the bulges 26 it is to be noted that the tube wall is stretched primarily laterally to leave rather short fillets 34 and'35 acrossthe tube I6. The pockets 36, Fig. 4, formed inside of the tube I0 inside of each of the bulges 25 are normally on the under side of the' tube Ill when the installation is made. These pockets 36 are sufiicient to set up the desired resistance to flow longitudinally of the tube I0 to induce lateral flow'through the connector tube 2, and yetrthe shape is such that no sound is evident in the installation. It is understoodof course, that in the-radiating heat installation?I water is circulating throughout the various pipes or tubes to maintain the fluid therewithin at the required temperature.

Now referring to Figs. -12, the supply and return flow lines 40 and 4l respectively each constituting lengths of the tubing I0 above described with the connector tubes 21 mounted thereon, are placed along the 'sides of the lower portion of a joist 42. In the form herein shown, the plaster backing is shown to be the now customarily employed plaster board 43. At the joist 42 along which the lines 40 and 4l are positioned, Fig. 10, a spacing strip or as herein shown, a plurality of spacing blocks 44 are secured to both sides of the joist 42, the thicknesses of these blocks 44 being close to but slightly larger than the diameter of the lines 40 and 4 I. Then across Y these blocks 44 are fixed, one on each side of the joist 42, the plaster board nailing or securing strips 45 and 46. This plaster board 43 is secured to the under sides of the strips 45 and 45 to terminate at their inner opposing edges to permit insertion of these lines 4D and 4l along the sides of the joist 42 and within the strips 45 and 46. Then the tubing 33 has one end secured in a connector tube 21 on the line 4l for example, Fig. 12, and is carried out across the ceiling and looped around to come back by its other end 41 to cross under the line 4l and fit in the connector tube 21 on the flow line 40. This looped arrangement of the tube 33 is carried directly against the plaster board 43 and secured in position by any suitable manner such as by staples 48, this securing means likewise retaining the lines 49 and 4I in their positions along the joist 42.

A six inch wide strip of metal screen 50 or plaster lath having openings therethrough limited in size to allow only sufficient plaster to flow therethrough to clinch on the top side, is placed over the pipes 40 and 4| and tacked along its edges to the strips 45 and 45, Figs. 10 and 12. Then, when the plaster 49 is applied, the screen 50, being spaced from the Iboard 43 by the undersides of the tubes 21, the plaster 49 will be withheld entirely from contact with the pipes 40 and 4l, while the tubes 33 will be embedded in the plaster 49 on each side of the screen 50. In this respect, reference is made to my prior Patent No. 2,338,090, issued January 4, 1944.

Thus it is to be seen that while the radiating tubes 33 are imbedded in the plaster 49, they pass under the flow lines 40 and 4l without having to be bent thereunder in order to reach the connector tubes on the other line. Also by reason of the lines 4l! and 4l further Ibeing spaced through the connector tubes 21 as above indicated these lines 40 and 4! are removed from the plaster 49 so that conduction loss from those tubes is negligible. The space between the strips 45 and 46 may be filled in with suitable insulating material over the lines 40 and 4|, or they may be left open as indicated in the drawing.

While I have herein shown and described my invention in the one particular form, it is obvious that many structural variations may be employed without departing from the sprit of the invention and I therefore do not desire to be limited to that precise form beyond the limitations which may Ibe imposed by the following claims.

I daim:

1. A tube cross connection comprising a tube with an outwardly localized bulged zone of the tube wall; said zone having a hole therethrough elongated transversely of the tube and generally elliptical in contour; and a connector tube of less diameter than that of said first tube and having an arcuate opening along one side, the chordal length of which opening is substantially equal to the major length of said zone hole, said connector tube being positioned transversely across said iirst tube to have its opening coincide With said hole; and means securing the two tubes one to the other; the said connector tube being approximately tangential to said irst tube.

2. A tube cross connection comprising a header tube; a localized outwardly bulged integral zone of the wall of the tube having a substantially elliptical hole therethrough and having its major axis transversely disposed across the zone; said zone being exteriorly convexly ycurved transversely of the tube; a cross tube having a substantially elliptical hole therethrough with its major axis parallel to its longitudinal axis, the over-all length of the cross tube hole being approximately equal to that of said header tube hole, said cross tube being positioned transversely across said Zone whereby the margins of both of said holes substantially coincide; and a brazed connection between said two tubes around said holes forming a fluid tight joint between the tubes; said zone having its outer wall spaced from the axis of the header tube to locate the axis of said cross tube that distance from said header tube axis substantially equal to the radius of the external surface of the header tube plus the radius of the external surl'ace of the cross tube.

JOSEPH L. BRADFIELD.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,205,703 Bowman Nov. 2l, 1916 1,674,131 Russell June 19, 1928 1,966,403 Durham July 10, 1934 2,192,904 Ferris May 12, 1940 2,338,090 Bradiield Jan. 4, 1944 2,387,154 Kalwitz Oct. 16, 1945 

